The invention relates to an aqueous folinate solution which is stable at refrigerator temperature.
Folinic acid is a metabolite of folic acid and is the active form to which folic acid is converted in the body. This conversion is inhibited by some cytostatic agents, such as methotrexate. In order to counteract this it is necessary to administer folinic acid, and the form of the folinic acid which should be administered pharmaceutically is the calcium folinate.
Usually, calcium folinate is administered by infusion or injection, and the dosages thereof are growing ever higher. Consequently, there is a demand for more concentrated solutions. Calcium folinate is good soluble at room temperature, but it is not stable and consequently cannot be stored sufficiently long. At refrigerator temperature, at which it is much more stable, high concentrations cannot be prepared. At the normal refrigerator temperature of 4.degree. C. crystallization may already occur at 15 mg/ml, and if by chance the refrigerator has been adjusted somewhat to the cold side and has a temperature of about 0.degree. C., this may already occur at 12 mg/ml. Consequently, there is a need for an aqueous folinate solution which is stable at refrigerator temperature, i.e. which will not crystallize at that temperature.